Snapshots of the 1054 nm pump laser envelope and the 1300 nm seed laser envelope interacting in a cold plasma (a) near the beginning of the simulations, with the seed still outside the plasma and the pump just entering the plasma and (b) near the end of the simulations, after the bulk of the seed and pump envelopes have exited the plasma. In (b) the dashed line on the left hand side is the ETW pump and the solid line is the PIC pump. The dashed line on the right hand side is the ETW seed and the solid line is the PIC seed. The vertical dashed lines indicate the boundaries of the 1 mm plasma slab; refer to the text for the other parameters of this simulation.
Profiles of the final seed laser envelopes (dashed for ETW, solid for PIC, dotted for LTW) after exiting the plasma for (a) cold, (b) 78 eV, (c) 142 eV, (d) 200 eV, (d) 365 eV, and (e) 525 eV cases. Due to the difference in group velocities, the PIC waveforms have been shifted to best overlap with the three-wave envelopes. The fine-scale spikiness in the PIC seed is due primarily to numerical errors in the simple algorithm employed to approximate the envelope from the full transverse electric fields, while the remnant traces of the counter-propagating fields are a numerical artifact of the directional diagnostic used to extract the left and right-moving modes of the EM fields on a staggered Yee grid.
Time series of normalized peak intensity vs time for (a) cold, (b) 78 eV, (c) 142 eV, (d) 200 eV, (d) 365 eV, and (e) 525 eV cases, showing predictions of the ETW (dashed), PIC (solid), and LTW (dotted) models. At time the peak of the seed and the peak of the pump meet close to the leading (left) edge of the plasma slab.
Parameters for the three-wave models ( is the linear Langmuir wave frequency and is the Debye length).
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